title: DNA damage response to different surface chemistry of silver nanoparticles in mammalian cells.
abstract: Silver nanoparticles (Ag NPs) have recently received much attention for their possible applications in biotechnology and life sciences. Ag NPs are of interest to defense and engineering programs for new material applications as well as for commercial purposes as an antimicrobial. However, little is known about the genotoxicity of Ag NPs following exposure to mammalian cells. This study was undertaken to examine the DNA damage response to polysaccharide surface functionalized (coated) and non-functionalized (uncoated) Ag NPs in two types of mammalian cells; mouse embryonic stem (mES) cells and mouse embryonic fibroblasts (MEF). Both types of Ag NPs up-regulated the cell cycle checkpoint protein p53 and DNA damage repair proteins Rad51 and phosphorylated-H2AX expression. Furthermore both of them induced cell death as measured by the annexin V protein expression and MTT assay. Our observations also suggested that the different surface chemistry of Ag NPs induce different DNA damage response: coated Ag NPs exhibited more severe damage than uncoated Ag NPs. The results suggest that polysaccharide coated particles are more individually distributed while agglomeration of the uncoated particles limits the surface area availability and access to membrane bound organelles.
authors.affiliation: Department of Biology, Centre for Tissue Regeneration and Engineering, University of Dayton, Dayton, OH 45469, USA.
authors.forename: Maqusood
authors.initials: M
authors.lastname: Ahamed
authors.forename: Michael
authors.initials: M
authors.lastname: Karns
authors.forename: Michael
authors.initials: M
authors.lastname: Goodson
authors.forename: John
authors.initials: J
authors.lastname: Rowe
authors.forename: Saber M
authors.initials: SM
authors.lastname: Hussain
authors.forename: John J
authors.initials: JJ
authors.lastname: Schlager
authors.forename: Yiling
authors.initials: Y
authors.lastname: Hong
mesh_terms: D000818:Animals; D018929:Cell Culture Techniques; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004249:DNA Damage; D053595:Embryonic Stem Cells / Q000187:drug effects* / Q000378:metabolism; D005347:Fibroblasts / Q000187:drug effects* / Q000378:metabolism; D015151:Immunoblotting; D053768:Metal Nanoparticles / Q000737:chemistry / Q000633:toxicity; D051379:Mice; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D012834:Silver / Q000493:pharmacokinetics / Q000633:toxicity*; D013499:Surface Properties
chemical_list: D012834:Silver